1. Field of the Invention
This invention relates generally to a video tape recorder and particularly to a tape speed control system of the video tape recorder.
2. Description of the Prior Art
Recently, a helical scan video tape recorder (HVTR) is widely used even in a broadcasting field. The most important advantage of the HVTRs is that it is easy to play back in slow motion mode, stop motion mode, and fast motion mode even in a reverse motion mode. This is because the HVTRs record one field video signal in a single oblique track on the video tape.
In a prior art system, the command signal is supplied to the HVTR in the form of a DC potential. In such a prior art system, the speed of a video tape is not able to be controlled so precisely. Therefore, when the tape speed is required near the zero speed, the tape speed becomes unstable. When the tape is advanced near the zero speed in order to determine an edit point in the stream of scenes for the editing purpose, the unstable tape advance causes misdecision of the edit point.